Travelers look at the length and nature of an overseas trip to decide whether to subscribe to a data roaming plan or buy a local SIM card to access mobile data.

For Henri Boodee, New Jersey-based president and CEO of Medical Affairs Consulting, the decision boils down to "cost and utility".

"If I am overseas only for a few days and have little need to make long voice calls, the hotel service usually is sufficient for extensive Internet access," Boodee said, adding that he would subscribe to a data roaming service for such trips.

For more extensive ones that stretch a few weeks, he would buy a local SIM card and then forward the local number to business associates who might need to contact him.

Bernard Gore, ICT Programme Manager at New Zealand Department of Labour, also based his decisions on the length of his trip. If he is on a trip that lasts up to three weeks or expects limited data usage, he would chose a data roaming service. If he is travelling for work or will be overseas for four or more weeks, he would get a local SIM card.

Several Twitter users told ZDNet Asia that they preferred to purchase local SIM cards over data roaming services due to the risk of bill shock.

Twitter user @mikomix noted that she would opt for a SIM card because "I don't want to risk being shocked by the bill again and again when using roaming".

User @jchowjs had the same view. With a local SIM card, there would be no worry of "getting charged for something I might not be aware of when I return", he said.

Twitter user @antoniaong would choose either a local SIM or unlimited data roaming plan when she plans to consume a high volume of mobile data. She noted that both were good choices as long as she was aware of how much she would be charged.

The Singapore government is among several countries that has set up regulation to ensure mobile operators help consumers better manage their data roaming usage and minimize bill shock.

Data roaming for convenienceHowever, Ken Wee, interim CEO and vice president of infrastructure and operations at Bridge Mobile, believes bill shock is only a perceived drawback of data roaming.

With proper education to inform users of data roaming plans and how to select the preferred operator's network, bill shock can be prevented, Wee said.

"Users can also opt to apply for roaming usage control features with their mobile operator in order to avoid bill shock," he added. These features will allow consumers, for example, to cap their data usage to a pre-determined amount and receive a text alert when they have reached that volume.

Others said they would opt for a data roaming service for its convenience, rather than have to buy a local SIM card.

Andrew Gogarty, director at Secon, said: "I would switch on data roaming purely for the reason that people can then still contact me via my number. With a prepaid SIM, nobody would know my number."

Twitter user @RasheedAB added that he would usually activate his data roaming service because he found it tiresome to keep changing his SIM card.

Wee added that activation of data roaming services is simple as subscribers can do so by sending an SMS or a USSD code, or contact their operator's customer support center.

To take advantage of data roaming services, he said consumers should check with their local mobile operator on the data service plans available. They also need to select the preferred operator's network when roaming to avoid bill shock, he added.

John Assiter from GOSIM.com shared another alternative--international SIM card. He explained that travelers can buy an international SIM card before traveling. The SIM card would allow them to receive free calls and SMS while abroad and calls or data usage will be cheaper than roaming with their home operator, he added.